HostGator: http://hostgator.com is a good host for Omeka training and for granting student access to Omeka installations, since it allows you to create individual FTP accounts that others can use.

Jumpbox: http://www.jumpbox.com/app/omeka a service that simplifies the process of installing open source software. JumpBox gives you the option to run a virtual machine locally on your Windows/Mac/Linux personal computer, or to purchase website hosting that includes Omeka already installed.